Centrifugal pump



May 16, 1967 T. E. JUDD CENTRIFUGAL PUMP Filed Feb. 10, 1966 FIG-4 INVENTOR. THOMAS E. JUDD BY W WM H IS ATTORNEY United States Patent C) 3,319,573 CENTRIFUGAL PUMP Thomas E. Judd, 1960 Browning Ave., Salt Lake City, Utah 84108 Filed Feb. 10, 1966, Ser. No. 526,433 4 Claims. (Cl. 103-403) The present invention relates to pumps and, more particularly, to a centrifugal pump designed to handle liquids containing considerable quantities of entrained solids such as food products, sewage, industrial slurries, and so forth.

In the past a considerable number of different types of centrifugal pumps have been devised. Those pumps which are presently used for the handling of liquids containing substantial quantities of entrained solids are of unusually large size. This is because of the fact that the usual im peller system provided must be designed to accept large amounts and large sizes of solids, to produce their proper outflow from the pump at a predetermined pressure.

The present invention is principally concerned with the reduction in the size of centrifugal pumps designed for handling solids-containing liquids. What is provided in the present invention is a centrifugal pump, of small physical dimension, which is capable of handling and pumping at usable pressures liquids containing substantial amounts of solid material. The pump relies upon the new principle of separating the solids phase out of the incoming, soli'ds-entraining liquid; shunting the solids (and a portion of the liquid phase as carrier thereof) more or less directly to the pump outlet; pumping a remaining portion of the liquid phase of the incoming liquid into a high-pressure stream; and directing the resulting stream into and in the direction of flow of the solids in the outlet so as to increase the momentum and the resultant pressure of the mixture thereat.

The primary channel or'passageway of the present pump is of suflicient size for handling the entrained solids of the incoming liquid. The volute, pumping passageway used is of smaller but gradually-increasing size in the preferred form of the invention, so that the stream may be applied directly to the solids to force the same, at high pressure, out of the outlet conduit of the pump.

Accordingly, a principal object of the present invention is to provide a new method of pumping liquids having entrained solids.

A further object is to provide a new and improved pump for pumping liquids having solids entrained therein.

An additional object is to provide a pump which substantially separates the solids phase of incoming slurries and other liquids and shunts this solids phase more or less directly to the outlet of the pump, a portion of the liquid phase of the incoming flow being pumped into a highpressure stream for introduction into and in the direction of flow of the previously separated solids phase.

A further object is to provide a new and improved centrifugal pump wherein that portion of the pump in which the centrifugal action is greatest is utilized to produce a high-pressure stream of liquid; this stream is used to increase the momentum of solids and such liquids as are more or less shunted from the inlet to the outlet of the pump.

A further object is to provide a new and useful centrifugal pump wherein the pump areas of least centrifugal effect are used for directing solids and some liquid of the incoming stream from the inlet of the pump, more or less directly to the outlet thereof, a majority of the liquid phase being generated in that portion area having greatest centrifugal eifect, to provide a high-pressure stream to be introduced behind the shunted solids and in the direction of the outlet flow.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings in which:

FIGURE 1 is a perspective view, partially cut away in sections for convenience of illustration, of a centrifugal pump incorporating the features of the present invention.

FIGURE 2 is a vertical section taken along the line 2-2 in FIGURE 1.

FIGURE 3 is a top plan of the top surface of the impeller used in the present invention.

FIGURE 4 is a plan of the reverse side of the impeller used in the structure.

In FIGURE 1 the centrifugal pump 10 of the present invention is shown to include a back plate 11 and a front plate 12, the two plates being bolted together by means of attachments 13 and the use of a sealing gasket 14. For convenience of illustration the attachments 13 are shown only two in number; these may be any desired number.

Back plate 11 assumes a configuration as generally indicated in FIGURE 2 and is provided with means for accommodating a sealing journal 15 the latter of which receives impeller shaft 16. Impeller shaft 16 is driven by an engine or a motor M shown schematically in FIGURE 1. Shaft 16 is keyed by means of a Woodrutf key or by other means 17 to the rearwardly-extending boss 18, see FIG URE 2, of impeller 19. Centrifugal impeller 19 is disposed in impeller chamber C and includes an impeller plate 20, in general form resembling the segment of a sphere, and also plural front impeller blades 21 and plural rear impeller blades 22. Both front and rear impeller blades are preferably radially-directed outwardly as indicated in FIGURES 3 and 4. The impeller 19 may be substantially the same as that indicated in the applicants United States Patent No. 3,190,226, entitled Centrifugal Pumps. The disclosure in this patent is now fully incorporated herein by way of reference. The subject impeller will, of course, operate in substantially the same manner as the impeller in the above-referenced patent.

Front plate 12 is a formed and preferably cast member which includes, for the inlet I, an inlet attachment flange 23 provided with a plurality of mounting apertures 24. This flange will be attached to flow conduit bringing to the pump the inlet liquid, liquid and solid mixture, or slurry.

Inlet attachment flange 23 is integrally formed with medial inlet chamber 25. The latter is directed inwardly, see FIGURE 2, to approach a central portion 26' of the impeller 19. Medial inlet chamber 25 is contiguous with a flat medial portion 26, which itself is contiguous with an auxiliary, outlet volute channel 27. Outlet volute chan nel 27 may be integrally formed with the remainder of front plate 12. It will be noted that the volute outlet channel 27 commences at approximately point A and gradually increases in size to point B, at which point or area the same joins main outlet channel 28 to constitute a conjoint outlet channel 29. Conjoint outlet channel or conduit 29 is provided with outlet attachment flange 30, for the outlet 31, which itself includes a plurality of mounting attachment apertures 31.

In FIGURE 1 the structure is broken away to reveal the interior of the pump. It will be understood that the volute outlet channel progresses regularly from point A to point B in a progressively-widening manner. The main outlet channel 28 communicates with inlet chamber 25 by means of a through-aperture 29. correspondingly, it will be understood that the volute outlet channel 27 is conjoint with main outlet channel 28 such that both provide conduction of fluid through the respective channels to conjoint outlet channel 29 and through outlet attachment flange 30. Outlet attachment flange 30, of course, will provide the outlet passageway 31.

With reference to the impeller 19 it will be seen from the drawing that the same is driven by motor or drive means M via impeller shaft 16 keyed thereto. A revolvement of the impeller, see FIGURE 3, for example, is produced 'by drive means M, and through centrifugal force a rapid flow of inlet fluid from the area proximate the medial portion 26 of the impeller to the outer regions thereof is generated which results in a very high, fluid velocity at the tips of the impeller blades 21. The action of blades 22 on the reverse side of the impeller is simply to evacuate this region of fluid and entrained solids as might otherwise deter continuous satisfactory operation of pump over long periods of time. See in this regard the above-referenced patent.

With reference to FIGURE 2 it will be seen that the action of the centrifugal pump is to force rapidly a portion of the liquids and substantially all of the solids of the fluid along a course R through the main outlet channel 28 (see FIGURE 2) and also to force a high velocity stream of liquid along course S, to join the aforementioned stream at the beginning of conjoined outlet channel 29. Hence, any solids entrained in the incoming flow will be directed primarily through main out-let channel 28 to conjoined outlet channel 29. This is especially the case where, as shown, the flat portion 26' is designed to be quite close in proximity with the impeller and its blades 21.

'Now the flow through volute outlet channel 27 is a very rapid, high-pressure and high-speed flow which develops appreciable pressure. This is so because the volute is designed to be proximate the outer periphery area of the impeller. It will be noted that this stream through the volute channel will be relatively free of all foreign matter such as sewage or other solid particles. This is so because the space or constriction means P between the impeller and the portion 26 is very small and hence does not permit passage of solids therethrough. (Of course, any fine-grained matter which does wedge in this area will tend to be carried through because of the force of the liquid through the action of the pump. In this regard it is especially important that passage into chamber C beyond space P rapidly increase in area so that the clogging tendency of solid particles passing through space P be substantially minimized.)

The high-velocity stream coming through the graduallyincreasing volute channel 27 will, through the kinetic energy produced, supply increased momentum to the solid particles of the material being pumped which come through medial inlet chamber 25 and proceed directly through main outlet channel 28 to a conjoint outlet channel 29. It is this rapid stream which produces a highpressure exhaust through outlet attachment flange 30.

What is provided, therefore, is a relative relationship between the impeller and the volute channel such that a mechanical separation of a portion of the liquid from the remaining liquid and solids entrained therein is achieved. The smaller size liquid channel, i.e., the volute channel, acts to collect from the periphery of the impeller a relatively clean stream of high-velocity, high-pressure liquid. This stream of liquid is introduced into the larger, solid-handling chamber at a point near the outlet (ma-in outlet channel 28) of the pump. 'By this unique concept the inventor is enabled to handle large size solids, but

with an impeller blade system of much smaller size than will be present in the art. In the present invention there is a channel of required clearance size, considering anticipated sizes of solids in the incoming stream, which routes, more or less directly through a small centrifugal action, to the pump outlet. The remaining portion of the pump comprises the volute channel which, through high centrifugal action, presents a high-velocity, highpressure stream of fluid to urge the solids out of the outlet at 31. Thus, the size of the pump required to handle such solids is materially reduced over prior art.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. A centrifugal pump comprising a structure defining a centrifugal pumping chamber, a centrifugal impeller operatively disposed in said chamber, said impeller having a convex blade supporting surface provided with a vaneless central portion and a peripheral bladed fluid energizing portion in said chamber, means sealingly journaled in said structure and centrally connected to said impeller and extending rearwardly thereof for driving said impeller, an inlet chamber for admitting fluids containing solids therein to said impeller chamber, said inlet chamber having a restriction therein extending circumferentially of the impeller, and defining a circumferentially spaced liquid phased auxiliary channel about the peripheral bladed portion, means defining a main outlet chamber communicating with said inlet chamber proximate the central vaneless portion of the impeller, said auxiliary channel and said main outlet chamber merging in a downstream direction whereby the energized pressure fluid from the auxiliary channel engages the solids entrained in said main outlet chamber fluid and forces the entrained solids in a downstream direction.

'2. The pump of claim 1 wherein said main outlet chamber provides a flow path disposed out of registry with and shunted across said impeller.

3. The pump of claim 1 wherein said auxiliary channel defined by said restriction comprises a volute channel of progressively-increasing size as it advances toward said outlet chamber.

4. Structure according to claim 1 wherein said impeller is provided with upstanding vanes proximately disposed said restriction as they pass underneath the latter.

References Cited by the Examiner UNITED STATES PATENTS 3,190,226 6/1965 Judd 103-1 15 FOREIGN PATENTS 226,536 3/1963 Austria. 534,355 1/1955 Belgium. 1,006,340 4/1957 Germany. 1,046,502 12/ 1958 Germany.

928,415 6/ 1963 Great Britain.

DONLEY I STOCKING, Primary Examiner.

HENRY F. RADUAZO, Examiner. 

1. A CENTRIFUGAL PUMP COMPRISING A STRUCTURE DEFINING A CENTRIFUGAL PUMPING CHAMBER, A CENTRIFUGAL IMPELLER OPERATIVELY DISPOSED IN SAID CHAMBER, SAID IMPELLER HAVING A CONVEX BLADE SUPPORTING SURFACE PROVIDED WITH A VANELESS CENTRAL PORTION AND A PERIPHERAL BLADED FLUID ENERGIZING PORTION IN SAID CHAMBER, MEANS SEALINGLY JOURNALED IN SAID STRUCTURE AND CENTRALLY CONNECTED TO SAID IMPELLER AND EXTENDING REARWARDLY THEREOF FOR DRIVING SAID IMPELLER, AN INLET CHAMBER FOR ADMITTING FLUIDS CONTAINING SOLIDS THEREIN TO SAID IMPELLER CHAMBER, SAID INLET CHAMBER HAVING A RESTRICTION THEREIN EXTENDING CIRCUMFERENTIALLY OF THE IMPELLER, AND DEFINING A CIRCUMFERENTIALLY SPACED LIQUID PHASED AUXILIARY CHANNEL ABOUT THE PERIPH- 